If you're looking for synonyms for the phrase "is quick", there are plenty of options to choose from. Some alternatives could be "is fast", "is swift", "is speedy", or "is rapid". Other possible synonyms could include "is prompt", "is efficient", "is expeditious", or "is brisk". Depending on the context, other descriptors that might work could include "is snappy", "is nippy", "is sprightly", or "is agile". Ultimately, the best synonym will depend on the specific situation and the tone that you're trying to convey. So whether you're writing an essay, a business report, or just a quick email, there is sure to be a great synonym out there to help you convey your meaning in the most effective way possible.